Retaining-valve device.



TTNTTE TATE ATENT FFT@EQ WALTER. V. TURNER, OE EDGEWOOD, PENNSYLVANIA,ASSIGNOR TO THE EVESTING- HOUSE AIR BRAKE COMPANY, OF PITTSBURGH,PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

RETAINING-VALVE DEVICE.

To aZZ 'whom it may concern Be it known that I, lWALTER V. TURNER, acitizen of the United States, residing at Edgewood, in the county ofAllegheny and State of Pennsylvania, have inventedV new and usefulImprovements in Retaining- Valve Devices, ofewhich the following is aspecification.

This invention relates to pressure retaining valves, and moreparticularly to. those employed in connection with fluid pressure brakesfor retaining a certain degree of pressure in the brake cylinderl inreleasing the brakes, so as to holdrthe bralres applied while theauxiliary reservoirs are being recharged. The degree of pressure atwhich the retaining valves are adjusted should be low enough to permitmovement of the train by the engine with the brakes a Jplied at theadjusted pressure, but it is also desirable that the higher pressureexisting in the brake cylinder at the time of releasing the bralresshould not drop down too rapidly to the pressure of the retaining valve,in order to enable the auxiliary reservoirs to be substantiallyrecharged before the minimum holding pressure is attained. This isparticularly desirable in grade operation where the grade is heavy, asthe higher braking pressure thus temporarily retained is of course moreeffective to hold the train in check. For the above reason, theretaining valve Outlet orifice for air released from the brake cylinderis usually of small size, and 011 this account is sometimes liable tobecome clogged with dirt or moisture.

The principal object of my invention is to provide a retaining valvedevice having a comparatively large outlet not liable to become cloggedand means for restricting the rate of flow therethrough.

In the accompanying drawing; Figure 1 is a central sectional view of apressure retaining valve device embodying my improvement, Fig. 2 asimilar view, showing a slightly modified form of my improvement; andFig. 3 an elevation of the pressure retaining valve device.

As shown in Fig. 1 of the drawing, a pressure retaning valve casing 1 isprovided having a chamber 2 containing the usual weighted retainingvalve 3. Fluid 'released from the brake cylinder is conveyed throughpipe 4 from the triple valve exhaust port or Specfication of LettersPatent.

Application filed March 29, 1911.

Patented GetH 111,1913.

serial no. 817,785.

o otherwise to the passage 5 in Casing 1, and

the usual cock 6 is adapted to connect said passage either with anatmospheric eXhaust port 7 in one position or with a passage 8 which isControlled by the weighted valve 3, in another position. According to myinv-ention, the outlet for fluid admitted to chamber 2, upon the liftingof the retaining valve from its seat, is provided with one or morechambers, such as the chambers 9 and j10, the Chamber 9 havingcommunication with chamber 2 through a restricted passage ll'in plug 12,and communication from chamber 9 to chamber 10 is by way of a restrictedpassage 13 in a plug lt. A passage 15 in plug 16 forms communicationfrom chamber 10 to the atmosphere. As the outlet from each of thechambers 2, 9, and 10 is restricted, it will be clear that the pressurein chamber 9 is less than that in chamber 2 and the pressure in chamber10 is less than that in Chamber 9, consequently, by reason of the factthat the lower the pressure in a chamber, the less will be the rate offlow of air therefrom through an orifice of given size, the rate of flowfrom Chamber 10 to the atmosphere will be less than where the airescapes from chamber 2 directly through a single restricted orifice ofthe same given size.

It will now be evident that by means of my improvement the rate of flowfrom the retaining valve is restricted while yet employing Outletpassages of sulficient size to prevent clogging with dirt and the like,

If desired, the passages 11, 13, and 15 may extend straight through theplugs 12, 14, and 16 instead of being staggered, as shown in thedrawing, although the latter arrangement is preferred, as the rate offlow of air is thereby reduced to some eXtent.

Any number of retarding chambers may be employed, according to thereduction 1n the rate of flow which is desired and the size of therestrictino orifice employed.

The construction hown in Fig. 2 is substantially the same as that shownn'Fig. 1, except that the retarding chamber device 1s arranged in theupper portion of the retaining valve casing.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent, is:

1. A pressure retaining valve devlce comprising a casing, a retainingvalve having an air Outlet, and a chamloer in said Outlet provided Witha restricted inlet port and a restricted Outlet port.

2. A pressure retaining valve device comprising a casing, a retainingvalve in said casing having an Outlet for the escape of fiuid, and aChamber having a restricted inlet port and a restricted Outlet port forthe passage of fluid escaping through said Outlet.

3. A pressure retaining valve device comprsing a casing, a retainingvalve in said casing for holding a predetermined degree of pressure inthe brake cylinder and having an Outlet for the escape of fluid past theretaining valve, and a chamher having a restricted inlet port and arestricted Outlet port for the passage of fluid escaping past saidretaining valve.

4. A pressure retaining valve device comprising a casing, a loadedretaining valve in said casing for holding a predetermined degree ofpressure in the brake cylinder and having an out-let for the escape offluid, and a series of chambers in said Outlet having restricted inletand Outlet ports for perniitting the escape of fluid from said retainingvalve.

5. A pressure retaining valve device comprising a casing, a loadedretaining valve in said casing for holding a predetermined degree ofpressure in the brake cylinder and having an Outlet for the escape offluid, and one Or more chambers having staggered inlet and Outlet portsfor permitting the escape of fiuid through said Outlet.

6. A pressure retaining valve device comprising a casing, a loadedretaining valve in said casing for holding a predetermined degree ofpressure in the brake cylinder and having an Outlet for the escape offluid, and a series of chambers in said Outlet, each provided With arestricted inlet port and a restricted Outlet port for the passage offiuid escaping from the retaining valve.

In testmony Whereof I have hereunto set set my hand.

WALTER V. TURNER.

Witnesses:

A. M. CLEMENTS, '13. C. SWARTZWELDER.

Copies of this patent may be obtained for five cents each, byaddressing' the Commissioner of Patents, Washington, D. 0.

